Hot melt thermoplastic adhesives have been widely used in industry for adhering many types of products and are particularly useful in applications where quick setting time is advantageous. Oftentimes it is desirable to dispense the adhesive as a spray. Prior art adhesive spray dispensers have included a spray head or gun which is supplied with hot melt adhesive in a molten state from a supply thereof such as a melt pot. Such dispensers are suitable for many applications and especially those applications requiring dispensing of large quantities of adhesive. However, the time and cost associated with starting up and shutting down these spray dispensing systems makes them not well suited for those applications where there is a need to spray relatively small quantities of adhesive at irregular intervals.
Another type of hot melt adhesive dispenser uses a solid adhesive typically in cylindrical stick form that is melted in the dispenser on demand. Different mechanisms have been used to advance the adhesive into and through a melt chamber or region, including rachet-type feed mechanisms, cocked ring-type feed mechanisms, and pneumatic feed mechanisms. An exemplary pneumatic hot melt adhesive dispenser is the Hysol 4000 dispenser sold by The Dexter Corporation of Seabrook, N.H. These dispensers, however, have not been known to issue a spray of adhesive. Instead, usually an adhesive bead is dispensed from the nozzle of the gun.
Accordingly, a need exists for a melt-on-demand hot melt adhesive spray dispenser, especially in the form of a hand-held, easily manipulable self-contained unit.